Blackbirds under threat from mosquito-borne virus
Usutu virus was first detected in the UK in 2020.
The British Trust for Ornithology (BTO) is asking the public to take part in a new survey to help it monitor the impact that Usutu virus is having on UK blackbirds.
The mosquito-borne virus was first detected in the UK in London in 2020. Since then, blackbird numbers, which were already in decline, have decreased much more strongly in the Greater London Area. There is also evidence of a wider decline in the south of England.
The virus’ spread has been linked to climate change. It was first identified in South Africa and has been present in mainland Europe for three decades. It is now considered to be endemic in South East England.
The BTO researchers hope that the Blackbirds In Gardens survey will help them to form a clearer picture of the possible spread and impact of the virus on blackbirds in a wide range of different locations, both urban and rural.
Usutu virus can be transmitted to humans. However, the bird-biting mosquitoes which carry it rarely bite humans and infections in people are mainly asymptomatic.
The survey is part of Vector-Borne RADAR, a government-funded project being run in partnership with the Animal and Plant Health Agency (APHA), the UK Health Security Agency, and the Zoological Society of London.
Arran Folly, a senior scientist at APHA and Vector-Borne RADAR project lead, said: “Our Vector-Borne RADAR project is helping to develop a better picture of emerging mosquito-borne viruses and the findings from BTO’s Blackbirds In Gardens survey will be invaluable in building a better understanding of how the virus could be impacting our blackbird populations.
“I would urge any garden owners to take part and help us keep track of this virus.”
Those wishing to take part in the survey can sign up here.
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